Lying in the sun for seven straight days sounds great when you book your ticket at home during a blizzard, but some of us get antsy with that much down-time. Fortunately, most beach destinations also are great places to take up a water sport, many of which are easier to learn than you may imagine.

SCUBA DIVING
Believe it or not, scuba diving is one of the easiest and most accessible water sports that a beach-goer can take up. It's also one of the most magical, especially in the Caribbean. There's nothing quite like gliding weightlessly 40 feet below the surface, a foreign traveler in a vibrant and utterly fascinating underwater world.

What it takes: A standard Open Water diver certification course lasts three to seven days, and includes classroom time, several confined-water practice sessions (usually in a swimming pool), and four dives in the ocean, and the course typically gives you a fair amount of free time after the lessons and classroom work. Scuba gear usually is included in the price of the course, though it's nice to get a mask and fins that fit right. A Discover Scuba course allows you to experience scuba diving in just a few hours; if you decide to continue, the course is credited toward the full Open Water certification. The Professional Association of Diving Instructors established these courses, and once you've gotten your Open Water card you can dive most places in the world. Some resorts also offer courses designed for kids as young as eight years old.

Who can do it: Diving is not a strenuous sport. In fact, you're instructed not to exert yourself, in order to keep your breathing slow and steady. That means virtually anyone can do it: young or old, thin or hefty, athletic or not—there are even programs for disabled divers. You always dive in pairs ("buddies," in diver lingo), so it's the perfect sport to take up with your spouse, parent, child, or best friend.

Where to go: There are literally hundreds of places in Mexico, the Caribbean, and Central America with great diving and first-rate dive shops—it's hard to go wrong. One favorite is Roatán, the largest of Honduras' Bay Islands, which attracts many first-timers for its forgiving conditions (warm water, little current, and access to the globe's second-largest barrier reef), affordable prices, and a friendly noncompetitive atmosphere. The island has numerous dive shops and resorts, with classes beginning virtually every day.

Tip: If you're already an experienced Open Water diver, try something new like shore diving in Bonaire or cavern diving in cenotes (sinkholes connected by underground rivers), south of Playa del Carmen, Mexico.